A #53 drill measures 0.0595 inch (1.511 mm). The closest fractional drill is 1/16" (0.0625") and the closest metric drill is 1.5 mm (0.0591"). It is the standard tap drill for #1-64 and #1-72.
What are the #53 drill equivalents?
| Drill | System | Decimal (in) | mm | Difference (in) |
|---|---|---|---|---|
| #53 | number | 0.0595 | 1.511 | 0 |
| 1.5 mm | metric | 0.0591 | 1.500 | -0.0004 |
Drill sets that include this size
Number and letter sizes come in indexed sets; buy the set rather than single drills.
What speed should a #53 drill run?
| Material | RPM (HSS) | Feed (in/rev) |
|---|---|---|
| 6061-T6 aluminum | 12,839 | 0.0012 |
| 360 free-machining brass | 9,630 | 0.0011 |
| 1018 cold rolled steel | 5,136 | 0.0009 |
| 304 stainless steel | 2,568 | 0.0006 |
Starting points from conservative HSS drilling speeds. Small drills often call for more RPM than a benchtop drill press offers; run at the top speed and feed gently. Use cutting oil in steel and stainless, and clamp the work: never hold it by hand.
Cutting fluid for drilling
Frequently asked questions
What is a #53 drill in inches?
0.0595 inch, which is 1.511 mm. Number drills get smaller as the number rises, so the next number up is a smaller drill. If you do not have this exact size, 1.5 mm is within 0.0004 inch.
What tap uses a #53 drill?
It is the standard 75% thread tap drill for #1-64 and #1-72. Tap drills are chosen to leave about 75% of full thread depth, the balance of strength and tapping torque that published charts use.